1. Field of the Invention
The invention relates to a plug part for detachably connecting a torch neck of a gas-cooled welding torch to a socket part arranged on a hose package if need be by interconnecting a torch housing, having a cylindrical pipe element with a flange and an axially extending channel for a welding wire and a protective gas, and a union nut rotatably arranged on the pipe element, said union nut having an inner thread for connection to a corresponding outer thread on the socket part.
Furthermore, the invention relates to a socket part for detachably connecting a hose package to a plug part arranged on a torch neck of a gas-cooled welding torch, having an at least partially cylindrically formed end piece with an axially extending channel for a welding wire and a protective gas, and an outer thread for connection to a corresponding inner thread of a union nut of the plug part.
Finally, the invention relates to a connecting device for detachably connecting a torch neck of a gas-cooled welding torch to a hose package, wherein the torch neck comprises an above-mentioned plug part and the hose package comprises an above-mentioned socket part.
2. Description of the Related Art
Torch necks for welding torches of the relevant kind have, for instance, become known from WO 2011/014900 A1 or from DE 9216866 U1.
Usually, torch necks are detachably connected to the hose package or the torch housing and/or torch handle of a welding torch. This renders it possible for the welder to choose among torch necks of different design and to use the most suited one for performing the respective welding process, on the one hand, and to exchange the torch neck once it is damaged or contaminated, on the other hand. Usual connections between the torch neck and the hose package or torch housing are performed with appropriate threads or quick fasteners such as, for instance, bayonet fasteners. In addition to the necessary mechanical stability of the connection between the torch neck and the hose package and/or the torch handle or torch housing, the connection is also intended to ensure that substantially no protective gas will exit due to leakage. Since electrical energy is also transmitted via the connecting device, i.e. the plug part and the socket part, the connecting device is also intended to guarantee the appropriate electrical conduction. It is of advantage for welding if the torch neck is configured to be rotated at least within a certain range, so that the welding torch may always be held at an optimal angle to the welding seam intended.
The well-known connecting devices between the torch neck and the hose package and/or the torch housing of a welding torch frequently only meet with a part of the demands mentioned and are complex to handle.